Exam 1: Chapter 4 Flashcards
(71 cards)
1
Q
Composed of carbon, hydrogen, oxygen fuel all cells of body important for brain, nervous system, and red bloods cells under physiological circumstances yields 4 kcal/g recommended 40-65% of total kcal/day
A
carbohydrates
2
Q
usable form of carbohydrates
A
glucose
3
Q
storage form of carbohydrates
A
glycogen
4
Q
What foods contain carbohydrates?
A
grains, vegetables, fruits, dairy (milk, yogurt), protein (beans)
5
Q
most carbohydrates found in _____ sources
- such as….
A
plant
- fruit, vegetables, legumes, grains
6
Q
Plants use this to convert carbon dioxide, water, and sunlight into simple sugars and oxygen
A
photosynthesis
7
Q
some carbohydrates found in ______ sources such as dairy
A
animal
8
Q
regardless of source, all carbohydrates are derived from….
A
sun’s radiant energy
9
Q
water taken up by plant roots donate hydrogen and oxygen
carbon dioxide taken up by leaves donates carbon and oxygen
solar energy from sun converts these molecules to ______
A
glucose
10
Q
sugars, like monosaccharides and disaccharides are what?
A
simple carbohydrates
11
Q
starch (digestible), fiber (indigestible) and glycogen, polysaccharides, are what?
A
complex carbohydrates
12
Q
one sugar
simple sugar unit; most basic unit of carbs
A
monosaccharide
13
Q
name the monosaccharides
A
glucose
fructose
galactose
14
Q
major monosaccharide in the body "dextrose" - blood sugar from the breakdown of starches and disaccharides half of the sucrose model we can make it primary fuel fro cells oxidation of this yields ATP
A
glucose
15
Q
The synthesis of glucose from non-glucose precursors like lactose from working muscles
or glucogenic amino acids from body protein breakdown
or glycerol from triglyceride breakdown
should only be active in exercising or fasting state
A
gluconeogenesis
16
Q
“fruit sugar”
- fruit, honey
most commonly consumed in sugar-sweetened beverages as high-fructose corn syrup
forms half of sucrose model
converted to glucose in the liver; unconverted is stored as fat
A
fructose
17
Q
“milk sugar”
forms half of lactose model
converted to glucose in liver
A
galactose
18
Q
name the disaccharides
what do they all contain?
A
sucrose
lactose
maltose
all contain glucose
19
Q
table sugar
glucose + fructose
A
sucrose
20
Q
formed when two monosaccharides combine
A
disaccharides
21
Q
milk products
galactose + glucose
A
lactose
22
Q
malt sugar
formed when starch is broken down to two glucose
glucose + glucose
A
maltose
23
Q
contain over 1000 sugar units
“many sugars”
A
polysaccharides
24
Q
the two forms of polysaccharides in plants
A
digestible starch and indigestible fiber
25
animal form of polysaccharide
glycogen
26
storage form of carbohydrate for animals and humans
structure similar to amylopectin
this in liver ---> blood glucose
- 100 grams in the body
- 18 hours worth of glucose
this in muscle ---> only used in that muscle cell
- 400 grams in the body
glycogen
27
- stores glucose molecules in both amylase (long, straight chain of glucose) and amylopectin (highly branched glucose chain)
- principle carbohydrate found in plants
digestible starch
28
two types of indigestible fiber
insoluble and soluble
29
indigestible fiber that...
- does not dissolve in/ absorb water
- not fermented by bacteria in the colon
- aids in defecation and helps prevent diverticulosis
insoluble fiber
30
indigestible fiber that....
- dissolves in water
- slows glucose absorption, lowers blood cholesterol
- readily fermented by bacteria in colon
- promotes healthy gut microbiome
- promotes health of large intestine
soluble fiber (fermentable fiber)
31
Fiber added to food that may provide health benefits
| includes prebiotic - stimulates growth or activity of beneficial bacteria (probiotics) in the large intestine
functional fiber
32
health benefits of fiber rich food?
```
reduces risk of heart disease and stroke
reduces risk of diabetes
improves digestive tract health
promotes healthy body weight
risk of colon and rectal cancer lowers with higher fiber intakes
```
33
Recommended fiber intake
25 g/day for women
| 38 g/day for men
34
What happens if there is an excess, too much, fiber?
constipation
35
chelating agents that bind essential minerals
binders in fiber
36
majority of CHO come from plant sources such as grains that have different forms based on amount they have been processed. these forms are.....
refined
enriched
fortified
whole
37
nutrients have been removed
| - grains are stripped of the nutrient rich bran and germ layer. leaving only the starchy endosperm
refined
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nutrients have been added to replace ones removed
enriched
39
new nutrients have been added
fortified
40
minimal or no-precessing; grain retains original nutrients
whole
41
-slows glucose absorption ----> insulin release decreased -----> decreased cholesterol synthesis in the liver
inhibits absorption of dietary cholesterol
bile acid absorption rendered (bile acids made of cholesterol)
risk for cardiovascular disease and gallstones reduced
overall, blood cholesterol lowered
- what causes this?
soluble fiber
42
2 classes of food sweeteners (used in food/beverage preparation to add flavor)
sucrose is the benchmark for comparison of these two
nutritive
| non-nutritive/alternative/artificial
43
high fructose corn syrup, honey, maple sugar, table sugar
- kcal content varies
- metabolized to glucose readily
- sugar alcohols: 2.6 kcal/g, absorbed/metabolized to glucose slowly
nutritive
44
```
no kcal
sugar substitues
substantially sweeter than sucrose
safety determined by FDA
Aspartame (in diet coke) : contains the amino acid phenylalanine and cat be consumed by people with PKU
```
alternative/non-nutritive/artificial
45
Carbohydrate RDA based on amount needed tp supply brain and CNS without relying on ketones for energy
130 g/day for adults
46
Average U.S. intake of carbohydrates is how many grams?
What percent of calorie intake is this?
What is the recommended calorie intake?
180 - 330 g
50%
45-65%
47
it is recommended to focus carbohydrate intake on what foods?
fruits, vegetables, whole grains, and processed foods
48
this carbohydrate digestion begins outside the body
it softens fibrous tissues
- when starches are heated starch granules swell (Soaking up water)
makes carbs easier to chew, swallow, and digest
cooking
49
```
where carb digestion begins
this is where salivary amylase from salivary glands breaks starches to disaccharides
prolonged chewing releases more amylase
-short duration
minor contribution to digestion
```
mouth
50
```
acidic environment
salivary amylase is deactivated here
there is no further starch digestion
- minor contribution to digestion
peristalsis moves food to small intestine from here
```
stomach
51
in this organ
Pancreas releases enzymes into the duodenum
this pancreatic amylase produces monosaccharides and disaccharides
This organ's enterocytes release enzymes that break disaccharides into their respective monosaccharide
-maltase acts on maltose
-sucrase acts on sucrose
-lactase acts on lactose
small intestine
52
```
Monosaccharide absorption
glucose and galactose
- what type of transport absorption into enterocyte?
- absorbed with what?
fructose
- what type of transport into enterocyte?
- attracts ______, diarrhea potential
- some can be converted to _____
```
```
glucose and galactose
- active absorption
- sodium
fructose
- facilitated diffusion
- water
- glucose
```
53
Carbohydrate transport and metabolism
absorbed monosaccharides in enterocytes enter the _____ ______ for transport to the _____ which transforms fructose and galactose to glucose
portal vein
| liver
54
This organ can
- release glucose into bloodstream to maintain blood sugar
- store excess glucose as glycogen
- store excess glucose as fat
liver
55
In this organ
- minor amount of dietary carbs go undigested so....
- undigested carbs travel to the colon to be fermented by bacteria
- bacterial fermentation produces acids and gases
- short chain fats produces by bacteria are metabolized for energy by the bacteria
- this may promote health for colon
large intestine
56
deficient production of lactose enzymes
lactose in undigested and not absorbed
lactose is metabolized by large intestinal bacteria
- causes gas, bloating, cramping, discomfort in varied severity
- severe cases it is called _____ ______
prevalent mainly in Native American, Asian, African American ethnic groups
lactose maldigestion
| lactose intolerant
57
this occurs when your body's immune system perceives proteins in milk as foreign invaders and mounts an allergic reaction
milk allergy
58
After carbohydrates have been broken down or converted to glucose that can be used for.....
supplying energy
protein sparing
preventing ketosis
59
Name this carbohydrate function
- Red blood cells need this because they use glucose only
and have no mitochondria
- Brain and CNS use glucose mainly but can use ketones
-muscle cells and peripheral tissues use glucose ( and byproducts of fat breakdown)
supplying energy
60
byproducts of fat breakdown in the body during periods of starvation or low carb intake
ketones
61
Name this carbohydrate function
| - means supplying enough dietary carbs to prevent breaking down of body protein
protein sparing
62
under adequate carb intake, _____ is used for
- building/maintaining body tissues
under low carb intake
- body makes glucose from it in gluconeogenesis
under starvation
- body pulls it from vital organs
- this results in weakness, poor function, and possible failure/death
protein
63
breaking down fat stores for creation of usable form of energy (ketones)
occurs during prolonged fasting/starvation and low carb intake
- not enough glucose coming in via the diet so the diet breaks down fat stores into a metabolite the cells can use for energy
not dangerous for a normal person but it is for people with uncontrollable diabetes
what do carbohydrates do to this?
ketosis
| carbohydrates prevent ketosis
64
when blood glucose gets too high
| confusion and difficulty breathing
hyperglycemia
65
when glucose gets too low
| dizziness and weakness, coma, death
hypoglycemia
66
what two organs work together to control blood glucose?
pancreas and liver
67
The liver stores glucose as _____
glycogen
68
The pancreas produces 2 key hormones that are inversely related. What are they?
insulin
| glucagon
69
produced by pancreatic beta cells
released in fed state, when blood glucose is high
directs liver to store glucose as glycogen (glycogenesis)
directs muscle and adipose tissue to remove glucose from the bloodstream
prevents glucose from being made, prevents gluconeogenesis
LOWERS blood glucose
insulin
70
produced by pancreatic alpha cells
released in the fasted state, when blood glucose is low
causes the breakdown of liver glycogen into glucose (glycogenesis)
promotes glucose being made in the body (gluconeogenesis)
RAISES blood glucose
glucagon
71
additional hormone that controls blood glucose
released from adrenal glands in response to muscle activation/use (such as exercise)
"fight or flight" response
stimulates both liver and muscle glycogen breakdown
RAISES blood glucose
Epinephrine "Adrenaline
